Improvement in cupola-furnaces



UNTTED STATES PATENT OFFICE.

EZEKIEL C. LITTLE, OF ST. LOUIS, MISSOURI.

IMPROVEMENT IN CUPOLAfFURNACES.

Specification forming part of Letters Patent No. 184,161, dated November7, 1876; application led August 12,. 1876.

To all whom it may concern:

Be it known that I, EZEKIEL C. LITTLE, of St. Louis, in the county ofSt. Louis, and in the State of Missouri, have invented certain new anduseful Improvements in a Cupola or Melting Furnace 5 and do herebydeclare that the'followin g is a full, clear, and exact descriptionthereof, reference being had tothe accompanying drawings, and to theletters of reference marked thereon, making a part of thisspecification.

` My invention relates tothat elassof cupolafurnaces wherein the ai-r isadmitted in small and numerous jets, for the purpose of creating a moreperfect combustion of the fuel in the interior of the cupola; and Iitconsists in the construction and arrangement of the tuyeres dischargingair into the furnace, all as hereinafter more fully set forth.

In order to enable others skilled in the art to which my inventionappertains to make and use the same, I will now proceed to describe itsconstruction and operation, referr-ing to the annexed drawing, in which-Figure l is a side elevation of a cupola or smelting furnace embodyingmy invention. Fig. 2 is a vertical section, and Fig. 3 a horizontalsection, of the same. Fig. 4 is a detailed view of apart thereof.'

A represents the interior body of the cupola; B, the dotted line orlines of the bed. C is the air-chamber surrounding the furnace, "andprovided with doors I I. D1, D2, D3, and D4 are four series of tuyeres.E is the throat or tapping-hole; F, the bed-plate; G, the airpipes; H,the brick lining, and J the pit.

The object of my invention is to secure an active and uninterruptedmelting action, and to prevent clogging or bridging of congealed slagand chilled particles of iron, which form over the ordinary horizontaltuyeres when near the conclusion of the heat.

The novelty of my invention consists in the arrangement of a series oftuyeres, graduating in size from large to small, and placed at an angleverging toward the center of the interior of thecupola, the bottom ofwhich Vis made concave. The first or lower course, D1,

of tuyeres, which entirely surround the cupola,

is placed at an angle to meet the exact center of the concavity of thebottom of the cuthe courses of tuyeres pola. The second course, D2, isplaced at an angle of, say, about ten degrees nearer the horizontalline. The third and fourth courses, D3 and D4, are placed at the sameangle as the bottom course, D l. The object of placing at such angles isto create a more perfect .combustion of the fuel, and to force the heatdownward upon the melted iron.

The portability of the tuyeres enables me toA replace them if burned outon the ends, as they come ush or a little back of the -inner wall of thecupola; and they are adapted to all grades of fuel, for when used forcoal, and a stronger blast is needed, the upper course can be stopped upor closed oft', even while the blast is in operation, thereby creating astronger blast or pressure on the lower tuyeres or tubes. The lowertubes are pitched t0 consume the fuel in the interior bed .of thecupola. Y

Heretofore the fuel used with ordinary horizontal tuyeres has beencomparatively lost between the bottom of the tuyeres and the bottom orbed of the cupola; but by my arrangement, the tuyeres meeting theconcavity ot' the bed by their pitch or angle, the fuel is entirelyconsumed upon the melted iron by the blast being forced upon it. Thegreat angle also serves to prevent the melted iron from running backinto the chamber C While in'process of operation.

The chamber or drum C, that surroundsthe cupola, is ot' sufficient sizeto incase all of the tuyeres or tubes used, and the distance between themain body or outside or cupola proper and the outside drum is equal tothe length of the tubes. The drum is also provided with a sufficientnumber of doors or openings I, for the purpose of removing the portabletuyeres or tubes in case they should become derangedor burned out, andalso to enable me to stop ott' part of the blast in the event ofchanging the fuel used.

A. greater force of blast is needed for coal than for coke or thelighter grades of fuel; therefore, by shutting oft' part of 4theopenings the pressure is increased on the remainder. The doors alsoserve as a draft to the re before putting on theblast.

In front, at the tapping-hole E,'is attached a slag-catcher andiron-mixer, constructed as follows: N is a box or chamber attached tothe cupola, which receives the iron from the body of the cupola. Theslag that follows the molten iron into the box or chamber rises to thesurface of the melted iron, and is scraped oi' through an opening, b,and through the channel or gutter L attached to the side of the box,into the pit J under the cupola. The box K is provided with a cover, M,to protect the operatives while catching the molten iron.

It will be noticed that there are two tap- I pingholes-one, E, in thebody of the cupola,

and one, d, in the front of the chamber K, through the plate N. It isthe intention to keep the hole E in the body of the cupola open all thetime, and allow the iron to accumulate in the chamber K, and then drawnoff through the plate N. This plate is made separate from the box, andsits in slides, so that it canl be removed to facilitate the cleaningout of the box or chamber. In the top of the plate N is a small openingor cavity, e, so as to reach over and tap the hole E in the body Theseries of tubes or tuyeres, graduating in size and placed at differentangles vergying toward the center of the interior of the cupola, thelower course of said tuyeres being inclined on a line with the exactcenter 0f the concavity of the bottom, substantially as and for thepurposes herein set forth.

In testimony that I claim the foregoing I have hereunto set my hand this26th day of July, 1876.

EZEKIEL C. LITTLE.

Witnesses:

BENJAMIN SMITH BUCK, IRWIN E. LITTLE.

